Signs and Symptoms of Conjunctivitis
Conjunctivitis presents with conjunctival hyperemia plus additional inflammatory signs such as discharge, follicles, or papillary reactions, with specific etiologies including infectious, allergic, toxic, or immune-mediated causes. 1
Key Clinical Signs and Symptoms
General Signs
- Conjunctival injection (redness) - diffuse pattern suggests conjunctivitis, while sectoral patterns may indicate localized irritation 1
- Discharge - character varies by etiology (purulent, mucopurulent, watery, mucoid) 2
- Mattering and adherence of eyelids, especially upon waking 2
- Chemosis (conjunctival edema) 2
- Preauricular lymphadenopathy - especially with viral and chlamydial forms 2, 1
Symptoms
- Itching - strongest indicator of allergic conjunctivitis 1, 3
- Tearing 2
- Irritation or foreign body sensation 2
- Pain - severe pain should prompt investigation for other conditions 4
- Photophobia 2, 3
- Blurred vision - significant vision changes warrant further investigation 2, 4
Specific Types of Conjunctivitis
Viral Conjunctivitis
- Most common cause of infectious conjunctivitis 5
- Often begins unilaterally and becomes bilateral 1
- Watery discharge 4
- Follicular reaction of tarsal conjunctiva 2
- Preauricular lymphadenopathy 2
- May have associated upper respiratory infection 2
- Distinctive sign: subepithelial infiltrates in adenoviral conjunctivitis 2
Bacterial Conjunctivitis
- Second most common cause of infectious conjunctivitis 5
- Mucopurulent discharge 4
- Eyelids often matted shut, especially upon waking 4
- More common in children 4
- May remain unilateral 1
- Mattering and adherence of eyelids, lack of itching, and absence of history of conjunctivitis are strongly associated with bacterial etiology 5
Allergic Conjunctivitis
- Encountered in up to 40% of the population 5
- Intense itching - most consistent and characteristic sign 5, 3
- Bilateral presentation 3
- Mucoid discharge 3
- Chemosis and eyelid edema 3, 6
- Papillary hypertrophy of tarsal conjunctiva in severe cases 7
- Milky appearance of conjunctiva 7
- Stringy or ropy discharge 7
- Family history of allergy often present 7
Chlamydial Conjunctivitis
- Unilateral or bilateral presentation 2
- Bulbar conjunctival injection 2
- Follicular reaction of tarsal conjunctiva 2
- Mucoid discharge 2
- May have corneal pannus, punctate epithelial keratitis 2
- Preauricular lymphadenopathy 2
- May have associated genitourinary symptoms 2
Diagnostic Approach
History Elements to Assess
- Duration and time course of symptoms 2
- Unilateral versus bilateral presentation 2
- Character of discharge 2
- Recent exposure to infected individuals 2
- Contact lens wear and hygiene 2
- Associated systemic symptoms 2
- History of allergies, asthma, or eczema 2
- Medication use 2
Physical Examination Findings
- Regional lymphadenopathy, particularly preauricular 2
- Eyelid abnormalities: swelling, discoloration, ulceration 2
- Conjunctival assessment: follicles vs. papillae, distribution pattern 2
- Slit-lamp examination to evaluate:
Warning Signs Requiring Specialist Referral
- Severe pain 4
- Decreased vision 4
- Recent ocular surgery 4
- Vesicular rash on eyelids or nose 4
- History of rheumatologic disease 4
- Immunocompromised state 4
- Neonatal conjunctivitis 4
Distinguishing from Other Conditions
- Conjunctival hyperemia without discharge, follicles, or papillary reactions suggests simple hyperemia rather than conjunctivitis 1
- Perilimbal redness pattern may indicate more serious conditions like scleritis or uveitis 1
- Painful pupillary reaction suggests intraocular inflammation rather than conjunctivitis 6
- Contact lens wear can cause both isolated hyperemia and contact lens-associated conjunctivitis 1